From adult +‎ -hood


adulthood (usually uncountable, plural adulthoods)

  1. The state or condition of a human being once it has reached physical maturity, and is presumed to have reached a state of psychological maturity, to wit: once it has become an adult.
    Son, now that you have reached adulthood, you are in the time of your life during which you are expected to take responsibility for your actions and for your well-being.
  2. The time period of a human being's majority; the time during which a human being has reached physical maturity, and ending with its death.
    The boy entered adulthood by undergoing a rite of passage.
    The things learned in childhood will effect a person throughout its adulthood.